Bug 1830271

Can you attach the output of `oc -n openshift-ingress get deploy/router-default -o yaml` (or the deployment spec from must-gather if that is easier)?

Sorry, didn't mean to re-assign at this time.

Moving to 4.6.

Created attachment 1694842 [details]
oc -n openshift-ingress get deploy/router-default -o yaml

It seems like the "router-default" deployment is reporting incorrect status.  If the deployment reported Available=False in its status conditions, then the ingress operator would set Degraded=True in the clusteroperator's status conditions.

The "router-default" deployment specifies 2 replicas with 25% maximum unavailable:

    spec:
      replicas: 2
      # ...
      strategy:
        rollingUpdate:
          maxSurge: 0
          maxUnavailable: 25%
        type: RollingUpdate

The deployment has 1 available replica yet reports Available=True:

    status:
      availableReplicas: 1
      conditions:
      - lastTransitionTime: "2020-06-03T14:21:40Z"
        lastUpdateTime: "2020-06-03T14:21:40Z"
        message: Deployment has minimum availability.
        reason: MinimumReplicasAvailable
        status: "True"
        type: Available
      - lastTransitionTime: "2020-06-03T14:31:40Z"
        lastUpdateTime: "2020-06-03T14:31:40Z"
        message: ReplicaSet "router-default-f4c5b8bdd" has timed out progressing.
        reason: ProgressDeadlineExceeded
        status: "False"
        type: Progressing
      observedGeneration: 1
      readyReplicas: 1
      replicas: 2
      unavailableReplicas: 1
      updatedReplicas: 2

The deployment's maxUnavailable parameter has the following meaning:

    	// The maximum number of pods that can be unavailable during the update.
    	// Value can be an absolute number (ex: 5) or a percentage of total pods at the start of update (ex: 10%).
    	// Absolute number is calculated from percentage by rounding down.

The deployment's "Available" condition has the following meaning:

    	// Available means the deployment is available, ie. at least the minimum available
    	// replicas required are up and running for at least minReadySeconds.

If the maximum unavailable is ⌊ %maxUnavailable * spec.replicas ⌋ = ⌊ 25% * 2 ⌋ = 0, then that implies that the minimum available is spec.replicas - 0 = 2.  This minimum is not met, so the deployment controller should set Available=False per the API documentation.

Based on the above analysis, I am re-assigning this Bugzilla report to kube-controller-manager, which manages the deployment controller, which sets the deployment's status.

Per your configuration:

  strategy:
    rollingUpdate:
      maxSurge: 0
      maxUnavailable: 25%
    type: RollingUpdate

that one replica of the router fulfils minimal requirements, and that's expressed in status:

      - lastTransitionTime: "2020-06-03T14:21:40Z"
        lastUpdateTime: "2020-06-03T14:21:40Z"
        message: Deployment has minimum availability.
        reason: MinimumReplicasAvailable
        status: "True"

For now I'd suggest looking at the above, which will give you the availability of your deployment
and then for full availability compare .spec.replicas with .spec.readyReplicas.

I've opened https://bugzilla.redhat.com/show_bug.cgi?id=1844502 to fix the Progressing state in the mean time, until we'll get the new status we'll be working in the upcoming months.

Handy code for my previous suggestion lives here: https://github.com/kubernetes/kubernetes/blob/442a69c3bdf6fe8e525b05887e57d89db1e2f3a5/pkg/controller/deployment/util/deployment_util.go#L738-L745

I’m adding UpcomingSprint, because I was occupied by fixing bugs with
higher priority/severity, developing new features with higher
priority, or developing new features to improve stability at a macro
level. I will revisit this bug next sprint.

I'll work on getting the posted fix reviewed and merged in the upcoming sprint.

Verified with 4.6.0-0.nightly-2020-07-25-091217 and issue has been fixed.

Below three types are added
  - lastTransitionTime: "2020-07-27T07:56:49Z"
    message: 'The deployment has Available status condition set to False (reason:
      MinimumReplicasUnavailable) with message: Deployment does not have minimum availability.'
    reason: DeploymentUnavailable
    status: "False"
    type: DeploymentAvailable
  - lastTransitionTime: "2020-07-27T07:56:48Z"
    message: 1/3 of replicas are available, max unavailable is 1
    reason: DeploymentMinimumReplicasNotMet
    status: "False"
    type: DeploymentReplicasMinAvailable
  - lastTransitionTime: "2020-07-27T07:56:48Z"
    message: 1/3 of replicas are available
    reason: DeploymentReplicasNotAvailable
    status: "False"
    type: DeploymentReplicasAllAvailable

and one type is removed:
  - lastTransitionTime: "2020-07-27T01:59:34Z"
    message: The deployment has Available status condition set to True
    reason: DeploymentAvailable
    status: "False"
    type: DeploymentDegraded

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (OpenShift Container Platform 4.6 GA Images), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2020:4196